Fire-extinguishing composition comprising ethoxylated alkylphenol and ethylene glycol mono lower alkyl ether

ABSTRACT

AN IMPROVED FIRE-FIGHTING COMPOSITION OF AN ETHOXYLATED ALKYLPHENOL AND AN ETHYLENE GLYCOL MONO LOWER ALKYL ETHER HAS BEEN DISCOVERED. THIS IMPROVED FIRE-EXTINGUISHING COMPOSITION IS USEFUL AS A WETTING AGENT, EMULSIFYING AGENT, LOW-EXPANSION OR HIGH-EXPANSION FOAM AND PERFORMS EXCEPTIONALLY WELL IN THE PRESENCE OF BOTH FRESH AND SALT WATER.

United States Patent 3,578,590 FIRE-EXTINGUISHING COMPOSITION COM-PRISING ETHOXYLATED ALKYLPHENOL AND ETHYLENE GLYCOL MONO LOWER ALKYLETHER Darle Lee Nieneker, Austin, and Leslie Preston Williams,

Groves, Tex., assignors to Jefferson Chemical 'Company, Inc., Houston,Tex. No Drawing. Filed Aug. 19, 1968, Ser. No. 753,714 Int. Cl. A62d1/00; 1301f 17/42 U.S. Cl. 252--8.05 3 Claims ABSTRACT OF THE DISCLOSUREAn improved fire-fighting composition of an ethoxylated alkylphenol andan ethylene glycol mono lower alkyl ether has been discovered. Thisimproved fire-extinguishing composition is useful as a wetting agent,emulsifying agent, low-expansion or high-expansion foam and performsexceptionally well in the presence of both fresh and salt water.

BACKGROUND OF THE INVENTION The problem of extinguishing fires hasplagued mankind throughout recorded history. Today in sophisticatedsociety many improvements have been made and are being made to combatthis age-old problem. With increased industrialization and particularlythe exploitation of petroleum resources through petrochemicals, thescience and are of fire extinguishing has become quite sophisticated.Fires have now become classified into various categories which varyaccording to the material involved and according to the mode ofextinguishing a fire involving this material.

Our invention relates particularly to two classifications: those ofordinary combustible solids, or Class A materials, which include thingslike wood, cotton, paper, etc.; and Class B materials, which areflammable liquids such as gasoline, hexane, benzene and other aromaticsand other liquid flammable hydrocarbons. Of special interest are thevarious polar solvents such as acetaldehyde, methyl ethyl ketone,2-ethylhexanol, and the like. These polar solvents have previously beenextremely difiicult, if not impossible in some instances, to extinguishwhen burning.

Many methods of extinguishing fires and fire-extinguishing compositionshave been explored by those interested in fire safety. Varied methodshave been used, such as Water alone particularly for the Class A typefire mentioned above. In addition, dry chemicals have been used inattempts to extinguish many Class B fires. In attempts to smother thefires, many of these dry chemicals are used as a foam produced by mixingtwo chemicals, such as aluminum sulfate and sodium bicarbonate, whichcontain a foaming agent and a stabilizer.

Another method which has been often used in fighting Class B fires iswith mechanical foam solutions where the foam is made with liquidinducted into the water stream before it comes into contact with air toform the foam. These mechanical-type foam liquids or fire-extinguishingcompositions are generally classified as protein and nonprotein,synthetic compositions.

The protein-type concentrate usually contains a high molecular weightpolypeptide formed by the chemical hydrolysis of vegetable or animalproteins from which it is made. Various metallic salts are included withthese protein liquids to give strength to the foam bubbles in thepresence of heat and the foam-forming mechanical action itself. Proteinfoams by and large base their fireextinguishing ability upon theformation of a thick blanket of foam which smothers the fire. Proteinfoams are genice erally classified as a low-expansion foam. The variousexpansion-type classifications will be discussed hereinafter.

The synthetic mechanical foams are produced from concentrates whichcontain various types of synthetic detergents and are capable of foamformation in suitable foam-generating equipment. While there are severalsynthetic-type concentrates on the market, it is generally necessary tomaintain supplies of more than one concentrate in order to have afire-fighting capability against the various types of fires.Additionally, each of these different type synthetic concentratesrequires specialized equipment for the use thereof depending uponwhether it is high expansion, medium expansion, low expansion, anemulsification or a wetting agent. Thus, an installation, to havefire-fighting capability against a broad range of flammable hazards,must purchase various types of fire-fighting material and a variety ofequipment with which to use the specialized material.

Accordingly, it has been found that most of the commercially availablemechanical foam materials, both protein and synthetic, are substantiallyinelfective in fighting fires where polar solvents are involved.Accordingly, many fire-extinguishing concentrates are sensitive towhether they are used with salt water or fresh water. This is importantwhen it may be necessary to extinguish a dockside or shipboard firewhere a flammable water immiscible liquid is involved.

As hereinbefore mentioned, the fire-fighting compositions arecategorized according to various classifications of material. Variousfire-fighting compositions are generally called wetting agents,emusifying agents, low, high or medium-expansion foams. A wetting agentis generally used when fighting a Class A fire to improve the soakingcharacteristics of the water coming in contact with the flammablematerial.

An emulsifying agent is used in fighting a flammable liquid fire andacts to combine with some of the flammable material, emulsifying it,thus producing a firm of sorts on the burning material. High-expansionfoams are those which produce a foam of a volume between and 1,000 timesthat of the liquid used in fighting the fire. Medium-expansion foamsgenerally range from about 10 times to 100 times the volume of theliquid and those below a ratio of 10 to 1 are known as low-expansionfoams.

In copending application Ser. No. 561,342, filed June 29, 1966, nowabandoned, it was disclosed that a burning liquid fire could beextinguished by applying to the burning liquid a foam produced bypassing through an air expansion nozzle a mixture of water with 2 to 6volume percent of a nonionic surfactant having the formula: RO(CH CH O)H wherein R is selected from the class consisting of alkyl groupscontaining from 4 to about 20 carbon atoms and alykylphenyl groupswherein the alkyl chain contains from about 4 to about 15 carbon atomsand n is a number of from about 4 to about 30. This material, thoughacceptable for extinguishing burning liquid fires in certaincircumstances, had some inherent disadvantages. It was found that smallamounts of water introduced into the concentrate caused gelation,rendering the concentrate totally unusable for fire-fighting purposes.The resulting gelation makes the material useless for further fireprotection. As was also disclosed in the copending application, thenonionic surfactant had a relatively high freezing point. Even thoughethylene glycol was added thereto to reduce the freezing point to usabletemperature, the gelation problem still remained.

Accordingly, it is an object of our invention to provide a fire-fightingcomposition which is adaptable for the extinguishment of Class A andClass B fires.

It is a further objective of our invention to provide 3 a fire-fightingcomposition which is useful either in salt or fresh water.

It is a further object of our invention to provide a firefightingcomposition which will be useful over a broad spectrum of applicationsfrom wetting agent through highexpansion foam.

It is a further object of our invention to provide a firefightingcomposition which does not gel when contacted with a small amount ofwater.

It is a further object of our invention to provide a firefightingcomposition which produces a foam stable under conditions where it issubjected to an overhead water s ra F rther objects and advantages ofour invention will be apparent to those skilled in the art upon readingthe description which follows. Such objects and advantages are intendedto be included within the scope of our invention.

SUMMARY OF THE INVENTION Our invention relates to an improvedfire-fighting composition which is useful as a wetting agent,emulsifying agent or as an expanded foam in fighting Type A and Type Bfires, including polar solvent fires, and the method of fighting saidfires with our improved fire-fighting composition. More particularlythis invention is directed to an improved fire-fighting composition madeup of a solution of an ethoxylated alkylphenol having the formula:

@owmcmomr wherein R is a C to C alkyl group and n has an average valueof from 4 to about 30. The ethoxylated alkylphenol is mixed with anethylene glycol mono lower aklyl ether in such proportions that theether is present in the amount of about 0.1 to about 0.5 part by Weightper part of the ethoxylated alkylphenol.

The method of fighting fires involves incorporating the improvedfire-fighting composition of our invention into a water stream andexpelling the water stream to contact the burning material. If it isdesired to use the fire-fighting composition as a wetting agent oremulsifying agent, it is expelled along with water through a standardnozzle which does not produce an expanded foam.

When expelled through a nozzle which introduces air into the liquidstream, an expanded foam results and is applied to the burning material.The fire-fighting composition is introduced into the water stream suchthat it makes up about 0.5 to about 6 volume percent of the aqueoussolution, depending upon the type of fire involved and theclassification of use; i.e., wetting agent or or expanded foam. Wettingagents are usually applied to burning materials at the lowerconcentrations, whereas the foamed material is generally applied athigher concentrations.

DESCRIPTION OF THE INVENTION Our invention involves a fire-fightingcomposition adaptable to a broad-spectrum application to various typesof fires including Class A fires of combustible solids and Class B firesof flammable fluids, which include the hard-to-extinguish polar solventfires.

Our improved fire-fighting composition is essentially a two-componentsystem, which is blended together to form a homogeneous solution. Onecomponent is an ethoxylated alkylphenol having the general formula:

wherein R is a C to C alkyl group and n has an average value of from 4to about 30. The other component is an ethylene glycol mono lower alkylether where the alkyl group has from 1 to 4 carbon atoms, such asethylene glycol monomethyl ether, ethlyene glycol monoethyl ether,ethylene glycol monopropyl ether and ethlyene glycol monobutyl ether,etc. These two components are generally present together in amounts ofabout 0.1 to about 0.5 part by weight of the ethylene glycol mono loweralkyl ether per part by weight of the ethoxylated alkylphenol.

While this is essentially a two-component composition, it is alsopermissible to include in the concentrate a foam stabilizer such as highmolecular weight polymers of ethylene oxide, polyvinyl resins,polyglycols and the like. The use of these materials is described in US.Pat. 3,258,423. An especially effective foam stabilizer has been foundto be 2,0004,000 units of ethylene oxide in the polymer such as thecommercially available polyethylene polymer, Polyox WSR-35. As taught bythe aforementioned patent, these additives are included in an amount offrom about 0.5 to 5 wt. percent of the concentrate.

It is also possible to store the concentrate with varying amounts ofwater present. That is to say, it is equally useful when inducted intothe fire-fighting water stream as an aqueous solution as when theanhydrous concentrate itself is used. Of course it is best not toinclude too much water in the concentrate since the effectiveness of thematerial may be somewhat reduced. It is preferred that the amount ofwater be held to less than about 30% by weight.

When stored in an aqueous condition it is often advisable to includetherein a corrosion inhibitor such as sodium benzoate or sodium nitrateor some other well known corrosion inhibitor which is compatible withthis type of system. It is within the scope of our invention to includein our fire-fighting composition these additives as long as the abovetwo components, i.e., the ether and the ethoxylated alkylphenol, arepresent in the proportions hereinabove mentioned.

The use of this improved fire-fighting composition is not limited to anyone particular aspect, but is applicable to use as a wetting agent infighting fires of Class A substances such as wood, mattresses, textiles,cotton and other combustible solids.

It is also applicable for use as an emulsifying agent to act uponflammable fluids to form a thin emulsion layer on the top thereof. Andit is also useful in forming low, medium or high-expansion foams forfighting fires of Class B flammables such as aromatic distillates,benzene, toluene, xylene, gasoline, kerosene, fuel oil, jet fuel,hexane, heptane, octane, and the like. We have also discovered it to beparticularly useful in fighting previously very difficultly extinguishedfires involving polar solvents such as acetaldehyde, benzaldehyde,methyl ethyl ketone, ethyl acetate, butylacetate, and the like.

In addition, as the following examples will illustrate, ourfire-fighting composition is useful even in the presence of salt waterand extinguishes particularly difficultly controlled fires such as thepolar solvents and hexane. This is true even when the fire is kindled inthe presence of flashback hazards such as metal structure present in thefire pit.

Our foam has also proved to be stable when used in conjunction withwater deluge sprays. This situation often occurs when a flammable liquidbecomes ignited in a chemical plant or petroleum refinery or around astorage tank. Deluge sprays, while ineffective to extinguish the fireitself, are used to keep the structural metal from reaching atemperature at which its structural strength fails. Prior art foams havebeen found to disintegrate badly in the presence of a water deluge spraysystem.

The fire-fighting composition of our invention was found to benongelling upon contact with minor amounts of water and also is readilysoluble in water to form a homogeneous aqueous solution havingoutstanding fireextinguishing properties. Unlike many fire-fightingcompositions, particularly the protein-type material, our improvedfire-fighting composition does not deteriorate upon standing in storagenor does it present corrosion problems to the fire-fighting system inwhich it is to be used. However, one precaution is necessary when thematerial is stored as an aqueous solution concentrate. That is, it isnecessary to incorporate therein an effective amount of a corrosioninhibitor.

Our invention will be further illustrated by the following exampleswhich are intended to be merely for purposes of illustration and not tolimit the scope of our invention.

EXAMPLE I A test fire of 100 gallons of aromatic distillate (flashpoint, 20 F.; initial boiling point, 115 F.; end point, 165 F.; Reidvapor pressure, 7 p.s.i.) was fought using a commercially availableliquid protein base foam educted through a commercially available foamnozzle designed for use with protein foam rated by the manufacturer todeliver 3% by volume of the protein-based foam at a rate of 150 gallonsper minute. The fire was extinguished using the protein based foam inapproximately two minutes.

A like test fire of 100 gallons of the same aromatic distillate wasextinguished by the use of a concentrate made up of 80% of a 9 molethylene oxide adduct of nonyl phenol and 20% of ethylene glycolmonoethyl ether. This concentrate was educted and foamed through thesame commercially available equipment used with the proteintypeconcentrate into a stream of water in a ratio of 3% by volume of theconcentrate and 97% by volume of water. This mixture was expanded withair by the use of a commercially available expansion nozzle rated at 150gallons per minute and applied to the fire. The fire was extinguished bythis foam in approximately thirty seconds.

This example illustrates the improved fire-fighting properties of thefire-fighting composition of our invention.

EXAMPLE II In a test pit having a 400 square foot area, 150 gallons ofhexane, flash point 0 to 24 F., was allowed a thirty-second preburn.This pit also contained metal structures as flashback hazards. Inaddition, there were twelve 0.35-gallon per minute sprinklers over the400 square foot pit discharging water into the pit. The concentrate ofExample I was educted into the water stream to provide a 3% concentrateaqueous solution. The water/concentrate solution was expanded throughtwo lIO-gallon per minute nozzles and applied to the fire. The fire wasextinguished in one minute and thirty seconds.

The previous example illustrates the ability of the firefightingcomposition of our invention to extinguish a hydrocarbon fire involvinga flammable liquid having a very low flash point. It also illustratesthe stability of the foam produced using the concentrate of ourinvention in the presence of a water deluge spray. From this example, itwill be seen that our fire-fighting composition performs wells on lowflash point hydrocarbons and also retains a stable blanket in thepresence of foam interfering conditions.

EXAMPLE III Under the conditions and procedures followed in Example II,a test fire of 150 gallons of acetaldehyde was extinguished in thirtyseconds. This example illustrates the applicability of the fire-fightingcomposition of our invention to the extinguishment of fires involvingpolar solvents.

EXAMPLE IV Following the conditions and procedures of Example II, a testfire of 150 gallons of benzene was extinguished in forty seconds.Benzene has a flash point of approximately 12 F.

EXAMPLE V In a pit 120 feet by 14 feet having flashback hazards, 4,000gallons of aromatic distillates was ignited and allowed a two-minutepreburn. This fire was extinguished with a 1%" diameter, gallons perminute foam nozzle, using a 3% solution of the concentrate of Example I.The fire was extinguished in one minute and fifty seconds, requiringapproximately 200 gallons of the water/ concentrate solution orapproximately /a of a gallon per square foot of fuel bed.

Fires have also been extinguished where the fuel was gasoline, ethylether, acetone, isopropyl acetate, ethyl acetate, isobutyl acetate, fueloil and ethanol and aldehyde ether combinations. These tests wereperformed using standardly available equipment producing bothlow-expansion and high-expansion mechanical foams. These fires were alsocontrollable while additional fuel was being sprayed into the test firefrom an overhead line, simulating the problem involved when fighting afire in a manufacturing facility where a transfer line had becomeruptured spilling additional fuel into an ignited pool of fuel.

We have found that the fuel fires can either be extinguished utilizingthe composition of our invention by playing the foam at the base of thefire at its edge and progressively pushing the fire in front of itacross the pool of flammable liquid. This can also be done throughutilizing a foam chute which is a chamber in which the water/concentratesolution is foamed and discharged by flowing it into the flaming liquid.As the quantity of foam produced increases, the fire is pushed by thefoam until it is extinguished.

An additional advantage we have discovered in the practice of ourinvention is that there is practically no water lost through the foamnozzle due to dripping and that all the water expelled from the nozzleis included in the foam itself.

Obviously, from the foregoing teachings, many modifications andvariations of the present invention are possible. It is therefore to beunderstood that it is within the scope of the appended claims topractice the invention otherwise than is specifically described herein.

We claim:

1. An improved fire-fighting composition useful as a wetting agent,emulsifying agent or as an expanded foam, consisting essentially of aconcentrate solution of an ethoxylated alkyl phenol and an ethyleneglycol mono lower alkyl ether wherein the ethoxylated alkyl phenol isrepresented by the formula:

where R is a C to C alkyl group and n has an average value of from 4 toabout 30 and the ethylene glycol mono lower alkyl ether is present inthe amount of about 0.1 to about 0.75 part by weight of the ethoxylatedalkyl phenol and wherein the ethylene glycol mono lower alkyl ether is aC to C carbon atom ethylene glycol ether.

2. The composition of claim 1 wherein the concentrate solution is anaqueous solution comprising up to about 30% by weight water.

3. The composition of claim 2 wherein the aqueous solution contains acorrosion inhibitor.

References Cited UNITED STATES PATENTS 2,088,085 7/1937 Gross et al.252351 2,413,667 12/1946 Urquhart 2528.05 2,529,211 11/1950 Busse et al.2523 2,774,709 12/1956 Mayhew et al. 252351X 3,008,905 11/1961 Wedell252307 3,258,423 6/1966 Tuve et al. 2523 3,282,843 11/ 1966 Alburger25235 1X 3,457,172 7/ 1969 Stewart et al 2523 JOHN T. GOOLKASIAN,Primary Examiner D. J. FRITSCH, Assistant Examiner US. Cl. X.R. 2523,307, 311, 351

